The invention provides a multispectral image registering method based on the small component and the noise component. The invention first performs the earlier processing work of the scaling transformation, the area selecting, the reference point selecting and the like on the multispectral image, then uses the traditional method to perform the primary registration, uses the several minimum characteristic values to construct the cost function through computing the image autocorrelative matrix or covariance matrix, to look for the minimum of the cost function and realize the registration. The invention has good robustness and accuracy, which not only can correct the registration mistakes based on the methods of mutual information and the crosscorrelation and the like with higher registration accuracy.